[vsnet-chat 5584] Re: [AAVSO-DIS] Re: V 4742 Sgr

[Brian Skiff <Brian.Skiff@lowell.edu>]

>>  Any guesses on the type of variable star?  Maybe a Mira or SRB??

     Probably not a Mira, since usually the large amplitudes involved
would mean it would have already been discovered.  Probably a garden-variety
semiregular, amplitude likely to be something like half a magnitude with
a cycle-length of 3 or 4 months.

>>  ...our differences in V magnitudes are due to different comparison stars and
>>  their assigned magnitudes.

     Could be that or the extent to which both of you can calibrate your
color terms for such a red star.  You both might do well to hit a couple
of the "very red" stars from that list I prepared as well as more ordinary
Landolt and Cousins E-region standards.

http://ftp.lowell.edu/pub/bas/starcats/ubvri.red


\Brian

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